Keyboard



FIG. 1 is a perspective view of a keyboard showing my new design;

FIG. 2 is a front elevational view there of; and,

FIG. 3 is a front elevational view there of showing the keyboard in a use state.

The broken lines in the figures depict environmental subject matters which form no part of the claimed design. 

CLAIM The ornamental design for a keyboard, as shown and described. 